They are different ranks in a taxonomy hierarchy. The genus is more exclusive than the phylum.
Order:
Domain,
Kingdom,
Phylum,
Class,
Order,
Family,
Genus,
Species
The substance is called DNA.
The correct answer is false. Extinction of organisms is not solely cause by man. Even way before, extinction is already happening. It can be caused by natural or human causes. Natural causes includes volcanic eruptions, earthquakes, floods, etc.
